The overall objective of the research portion of this grant is to correlate the specificity of naturally occurring salivary antibodies against purified Streptococcus mutans cell wall and surface antigens with resultant caries of immunity in humans. Currently two populations are employed in the study: caries-prone and caries-resistant individuals. Using enzyme-linked immunosorbent assay (ELISA), parotid saliva and serum is being assessed for the level, specificity and isotype of antibodies to a variety of Streptococcus mutans cell wall and cell surface antigens. It is anticipated that the results of these studies will demonstrate the role of salivary IgA antibodies in protection against dental caries and will also demonstrate the specificity of antibodies of importance in defense against this oral disease.